Question about performance (i7 980x, 5970x2)

[hirsch]

Hello guys,

I had wanted to water cool my new system.

Parts to be cooled with water:
i7 980x
2 x XFX HD5970 Black Edition
Asus Rampage III Extreme

I've a Corsair Obsidian 800D and I planning to stick with the PA120.4 at the top of the case.

What about the performance, will the PA120.4 be enough (or which is the best 120x4 rad)? I will probaly use blocks from EK (Supreme HF, 5970 nickel plated, RIIE nickel plated). I'm kind a newbie at this, so all advice I can get is very helpfull!

Thanks!

Best regards
Fredrik K

[Church]

Will you overclock/overvolt? Do you expect to get silent setup aswell? Will you load both CPUs & GPUs at same time (folding and alike things), or it will be just for gaming?

[hirsch]

Will you overclock/overvolt? Do you expect to get silent setup aswell? Will you load both CPUs & GPUs at same time (folding and alike things), or it will be just for gaming?

I will definitely overclock, especially the CPU. About the noise, I'm thinking of using PWM (600-1300rpm) fans from Akasa, in a PnP setup.

Akasa APACHE S-Flow Fan Blade PWM 120mm
http://www.performance-pcs.com/catalog/images/akasa/AK-FN058_01.jpg

And yes, I will use the system for more then gaming, maybe some folding. Which means that both CPU and the GPUs will be used at the same time.

[Church]

Gentle Typhoons imho are best performance/noise wise fans of 120mm size. They are very quiet at 1000-1100 yet push decent ammount of air and even at 1850 they are as loud as Noisblockers at 1400. +They have ball bearing (=good for horizontal mounting, unlike sleeve bearing fans, which have reduced life in such way of mount).
I'd say that 4x120 rad is not enough for that overclocked hardware you described especially if simultaneously fully loaded. While it might be barely better then air cooling, temps will be far from good, or you'll have to ramp up fan speed alot outside silent range. Overclocked/overvolted i7 can dissipate ~ 250W of heat, each of 5970 ~ 300W. I'd like to put at least 6-8 x120 rad area for that. In ideal 3x120 for cpu, and 4x120 for both gpus, in two separate loops. It sounds like lot of moding to do to mount that much @obsidian. Though much simplier if you give up on all-internal mount, and put tripple rad outside case to hang on back of case.

[eXa]

FYI Single loop > separate loop

[Church]

eXa: for generic usage/gaming - yes. Not if one plans to fully load simultaneously gpu & cpu by folding/crunching. Then one needs excessive rads or at least thermally isolate by separating cpu loop, for cpu temps/overclock to not suffer from heat dumped by gpus.

[eXa]

Depends on how much the heat from the gpus affect the cpu. The redundancy from 2 pumps in the single loop shure is good to have when folding.

[Church]

GPUs are little affected by higher temps, CPU's overclock on the countrary is. That's why often people suggest 3x120 per o/c-ed & overvolted i7, while say it's enough 2x120 for 480/5970, even though these top GPUs can dissipate even more heat. Now problem comes when cpu & gpus dump that much heat in single loop at same time - for that you need for each of them 3x120 or imho smarter - to separate loops and have gpu loop relatively less rads, as temps there mater less. In Gabe's test of single vs dual loops he noted himself that for generic usage pattern (eg. gaming) rarely are cpus and gpus fully loaded at same time so it's better if all rads work for cooling all waterblocks in same loop ... except simultaneous full load of everything cases.
Of course, there is always option of ramping fan speed on rads to the max to keep temps in check even with underrad builds.

[hlonipha]

I dont think you can crunch with 2 x XFX HD5970 Black Edition (ATI).

Check this reviews out to get a better idea of the rad performance http://martin.skinneelabs.com/HWlabs480GTX-Review.html but honestly I dont think you will get good performance with just one rad to cool all of your parts.

[bladechai]

Hi there,

I have exactly the same set up but in a lian-li A77 and it has a 3x120 and a 2 x120 in series. it is overclocked to 4.2 and both my 5970s are at 880mHz. My mobo is also water cooled. MY ambient is 23 and i am getting 33 for CPU at 1.4v and 40 for the GPUs at 1.3v at rest. Cheers.

[Church]

bladechai: are those temps under full load of both cpu/gpu-s? I doubt it.

[hlonipha]

Hi there,

I have exactly the same set up but in a lian-li A77 and it has a 3x120 and a 2 x120 in series. it is overclocked to 4.2 and both my 5970s are at 880mHz. My mobo is also water cooled. MY ambient is 23 and i am getting 33 for CPU at 1.4v and 40 for the GPUs at 1.3v at rest. Cheers.

has to be idle temps :rolleyes:

[Church]

I wonder why people suply idle temps at all? They are simply unimportant, as even inadequate cooling in almost all cases will be more then enough to cool almost any hardware at idle load. It's load temps that need to be low enough for overclocked hw to be stable and for cooling still be within tolerable noise level.

[bladechai]

bladechai: are those temps under full load of both cpu/gpu-s? I doubt it.

idle. at full load, the gpus go to high 50s

[bladechai]

I wonder why people suply idle temps at all? They are simply unimportant, as even inadequate cooling in almost all cases will be more then enough to cool almost any hardware at idle load. It's load temps that need to be low enough for overclocked hw to be stable and for cooling still be within tolerable noise level.

I guess with your more than a thousand posts vs my 70 i have a lot more to learn.....

[Church]

bladechai: Don't take that rant personal. It was generic rant. I always thought why almost all people provide idle temps alongside load temps in reviews/tests when in reality they matter so little :). It just unnecessary doubles shown/listed data. +In liquid cooling it's hard to get low/lower then with air cooler temps (no need to aim for that though). LC is capable of quieter & more effective cooling at load, where it really matters for better overclocking and quieter cooling vs air.

[bladechai]

bladechai: Don't take that rant personal. It was generic rant. I always thought why almost all people provide idle temps alongside load temps in reviews/tests when in reality they matter so little :). It just unnecessary doubles shown/listed data. +In liquid cooling it's hard to get low/lower then with air cooler temps (no need to aim for that though). LC is capable of quieter & more effective cooling at load, where it really matters for better overclocking and quieter cooling vs air.

None taken... :)